Three-dimensional (3D) imaging technology has been playing an increasingly important role for a wide range of applications, including the production of movies and video games, computer-aided industrial design, orthotics and prosthetics, reverse engineering and prototyping, quality control and inspection, documentation of cultural artifacts, and the like. To facilitate the extensive use of three-dimensional imaging technique by ordinary people, electronic handheld 3D camera product configured with imaging optics have been developed. Due to its portability, such camera devices can be easily handled by the user to analyze a real-world object or environment as needed.
Generally speaking, 3D camera product is designed to collect data on the shape of the object and possibly its appearance, which is then recorded as data points within three-dimensional space. Once a point cloud of geometric samples on the surface of the subject has been obtained, these points can then be used to extrapolate the shape of the subject, for example be converted into a triangulated mesh and then a computer-aided design model. For most situations, it requires multiple scans from many different directions to produce a complete model of the object, usually at least one 3D view being obtained during one scan at a certain perspective. Multiple 3D views are then assembled into a full three-dimensional model, which is often referred to as a “stitching” process.
Various stitching algorithms have been developed, most of which require proper overlap between latest acquired view and previously acquired view to ensure successful and efficient stitching and thus enhance the quality of 3D modeling. For the handheld 3D camera or scanning device products which allow the user to operate freely, i.e. to collect three-dimensional views of the object from substantially random orientations or positions relative to the object, there may exist particular difficulties for the stitching process since a randomly captured view could only mislead the reconstruction, bringing extra burden on calculation rather than a desired result. Prior art does not provide guidance to the user between 3D view captures on how to appropriately locate the scanning device so that the 3D view to be captured may contain useful information for the stitching process. Rather, the operator shall use his or her own judgment on site, and it is often the case that with more scans being conducted, considerable computing time may be required, while the results might often be inaccurate.